Impact of a novel-covered colonic stent in obstructive colon cancer.

BACKGROUND: Although the short-term outcomes of bridge-to-surgery (BTS) procedures using self-expandable metal stents are favorable, concerns remain regarding worsened prognosis due to tissue injury in the tumor area. Herein, we describe a newly developed covered stent, the Kawasumi Jabara colonic stent™, designed to reduce tissue damage/injury associated with stent-related complications in BTS procedures. This study aimed to evaluate the efficacy and safety of the Kawasumi Jabara colonic stent as a BTS for obstructive colorectal cancer (OCC). METHODS: This multicenter retrospective observational study included 44 OCC patients who underwent BTS with stents at four facilities between September 2020 and November 2022. The groups of patients receiving the Kawasumi Jabara and non-covered colonic stents were designated Groups C and NC, respectively. Treatment outcomes related to stent placement and surgery were compared using propensity score matching (PSM) analysis. RESULTS: Groups NC and C (n = 34 and 10, respectively) showed no significant differences in sex, age, tumor location, histological type, Colorectal Obstruction Scoring System (CROSS) score, or cStage; however, the stent placement duration was shorter in Group C. No significant differences were found in terms of the technical and clinical success rates for stent placement. Stent dislocation was observed in 0 and 2 cases in Groups C and NC, respectively. PSM analysis between eight cases, each from Groups C and NC, revealed no significant differences in stent-related or surgical outcomes between the groups. However, regarding the gross injury score in the resected specimens, Group C had a lower score than Group NC (1.8 vs. 5.5), and the proportion of pathological tissue injury involving deeper layers was also lower in Group C (37.5% vs. 100%). CONCLUSIONS: Compared to conventional non-covered stents, the Kawasumi Jabara colonic stent™ demonstrated favorable safety during stent insertion, retention, and surgery, with only mild tissue injury.

Artificial intelligence for surgical safety during laparoscopic gastrectomy for gastric cancer: Indication of anatomical landmarks related to postoperative pancreatic fistula using deep learning.

BACKGROUND: Postoperative pancreatic fistula (POPF) is a critical complication of laparoscopic gastrectomy (LG). However, there are no widely recognized anatomical landmarks to prevent POPF during LG. This study aimed to identify anatomical landmarks related to POPF occurrence during LG for gastric cancer and to develop an artificial intelligence (AI) navigation system for indicating these landmarks. METHODS: Dimpling lines (DLs)-depressions formed between the pancreas and surrounding organs-were defined as anatomical landmarks related to POPF. The DLs for the mesogastrium, intestine, and transverse mesocolon were named DMP, DIP, and DTP, respectively. We included 50 LG cases to develop the AI system (45/50 were used for training and 5/50 for adjusting the hyperparameters of the employed system). Regarding the validation of the AI system, DLs were assessed by an external evaluation committee using a Likert scale, and the pancreas was assessed using the Dice coefficient, with 10 prospectively registered cases. RESULTS: Six expert surgeons confirmed the efficacy of DLs as anatomical landmarks related to POPF in LG. An AI system was developed using a semantic segmentation model that indicated DLs in real-time when this system was synchronized during surgery. Additionally, the distribution of scores for DMP was significantly higher than that of the other DLs (p < 0.001), indicating the relatively high accuracy of this landmark. In addition, the Dice coefficient of the pancreas was 0.70. CONCLUSIONS: The DLs may be used as anatomical landmarks related to POPF occurrence. The developed AI navigation system can help visualize the DLs in real-time during LG.

Efficacy of cooling therapy and α-lipoic acid derivative against chemotherapy-induced alopecia in an animal model.

Chemotherapy-induced alopecia is frequently induced by various regimens of chemotherapy and has a significant impact on mental health and quality of life. However, the effect of available current treatment for chemotherapy-induced alopecia is not sufficient. This study aimed to clarify the therapeutic effects and mechanism of skin cooling and the antioxidant α-lipoic acid derivative on chemotherapy-induced alopecia. We developed a chemotherapy-induced alopecia model of cyclophosphamide (120 µg/g) using Institute of Cancer Research mice. We used cooling therapy and α-lipoic acid derivative application as the treatments. We compared the alopecia score, hair bulb diameter, insulin-like growth factor-1 level, vascular permeability, and apoptosis between the control and treatment groups. The alopecia score significantly improved in each treatment group compared with that in the cyclophosphamide group. Hair bulb diameter significantly improved in the cyclophosphamide + cooling group compared with that in the cyclophosphamide group. The insulin-like growth factor-1 level and vascular permeability level was significantly retained and suppressed, respectively, in each treatment group compared with that in the cyclophosphamide group. The number of apoptotic cells in the vascular endothelium significantly decreased in the cyclophosphamide + α-lipoic acid derivative group compared with that in the cyclophosphamide group. In conclusion, cooling therapy and α-lipoic acid derivative facilitated recovery from chemotherapy-induced alopecia caused by cyclophosphamide through decreasing vascular permeability.

Association of immune-related expression profile with sensitivity to chemotherapy in esophageal squamous cell carcinoma.

Neoadjuvant chemotherapy (NAC) followed by surgery is one of the standard therapeutic approaches in Japan for patients with locally advanced esophageal carcinoma. Recently, the JCOG1109 study revealed that NAC with docetaxel, cisplatin and 5-fluorouracil (5-FU) (DCF-NAC) is superior to NAC with cisplatin and 5-FU, and has now become the standard preoperative chemotherapy. Using a microarray system, we have previously investigated the expression profiles of endoscopic biopsy samples from patients with esophageal squamous cell carcinoma (ESCC) before DCF-NAC (preNAC) and identified 17 molecules as biomarkers predictive of a pathologically complete response to DCF-NAC. Here, we re-grouped our previous dataset based on the histopathological response grade with the addition of several microarray profiles and conducted a re-analysis using bioinformatic web tools including DAVID, GSEA, UALCAN, and CIBERSORTx. We identified 204 genes that were differentially expressed between the highly resistant and sensitive groups. Some of these differentially expressed genes (DEGs) were related to the immune response and showed higher expression in the sensitive group. UALCAN showed that high expression of 28 of the top 50 DEGs was associated with a favorable prognosis (p < 0.25), and that this reached a significant (p < 0.05) level for 18 of them, suggesting that patients with high expression of these genes might have benefited from chemotherapy and thus had a better outcome. In preNAC biopsy tissues from a DCF-sensitive case, we demonstrated the presence of cells expressing mRNA for CXCL9, one of the prognosis-related DEGs. Our results highlight the association of immune-related expression profile in preNAC ESCC with the DCF-NAC efficacy.

Perceptions toward issues in cancer care for people with mental illness among psychiatric care providers: A questionnaire study.

OBJECTIVES: To reduce cancer care disparities in people with mental illness, this study aimed to quantify psychiatric care providers' perceptions regarding issues that are insufficiently addressed or difficult to address. METHODS: Psychiatric care providers at 23 psychiatric hospitals in Japan were surveyed using mail questionnaires. Respondents were asked to rate 15 items with four categories related to insufficiencies/difficulties in cancer care for patients with mental illness on a five-point Likert scale. We analyzed the proportion of respondents who answered "insufficient/difficult" for each item. RESULTS: A total of 255 (76.3%) psychiatric care providers responded. For questions related to the skills and attitudes of psychiatric professionals, 48.3%-58.4% of respondents perceived that efforts for supporting cancer screening and treatment were insufficient. For the questions related to collaborations between cancer and psychiatric care providers, 75.3% of respondents perceived that inpatient visits between psychiatric and cancer hospitals were insufficient. For the questions related to in-psychiatric-hospital medical systems, 50.2%-87.2% of respondents perceived that support for screening, diagnosis/treatment, and palliative care for psychiatric inpatients were insufficient/difficult. 41.9%-57.4% of respondents perceived that social services in the community were insufficient. CONCLUSIONS: This study clarified the level of insufficiency/difficulty perceived by psychiatric care providers regarding issues related to cancer care for people with mental illness. Psychiatric care providers are required to have knowledge and skills in cancer screening and treatment. To improve access to cancer prevention, treatment, and palliative care, it may be helpful to establish systems to promote coordination between cancer hospitals and psychiatric hospitals.

An intraoperative artificial intelligence system identifying anatomical landmarks for laparoscopic cholecystectomy: a prospective clinical feasibility trial (J-SUMMIT-C-01).

BACKGROUND: We have implemented Smart Endoscopic Surgery (SES), a surgical system that uses artificial intelligence (AI) to detect the anatomical landmarks that expert surgeons base on to perform certain surgical maneuvers. No report has verified the use of AI-based support systems for surgery in clinical practice, and no evaluation method has been established. To evaluate the detection performance of SES, we have developed and established a new evaluation method by conducting a clinical feasibility trial. METHODS: A single-center prospective clinical feasibility trial was conducted on 10 cases of LC performed at Oita University hospital. Subsequently, an external evaluation committee (EEC) evaluated the AI detection accuracy for each landmark using five-grade rubric evaluation and DICE coefficient. We defined LM-CBD as the expert surgeon's "judge" of the cystic bile duct in endoscopic images. RESULTS: The average detection accuracy on the rubric by the EEC was 4.2 ± 0.8 for the LM-CBD. The DICE coefficient between the AI detection area of the LM-CBD and the EEC members' evaluation was similar to the mean value of the DICE coefficient between the EEC members. The DICE coefficient was high score for the case that was highly evaluated by the EEC on a five-grade scale. CONCLUSION: This is the first feasible clinical trial of an AI system designed for intraoperative use and to evaluate the AI system using an EEC. In the future, this concept of evaluation for the AI system would contribute to the development of new AI navigation systems for surgery.

Development of a cross-artificial intelligence system for identifying intraoperative anatomical landmarks and surgical phases during laparoscopic cholecystectomy.

BACKGROUND: Attention to anatomical landmarks in the appropriate surgical phase is important to prevent bile duct injury (BDI) during laparoscopic cholecystectomy (LC). Therefore, we created a cross-AI system that works with two different AI algorithms simultaneously, landmark detection and phase recognition. We assessed whether landmark detection was activated in the appropriate phase by phase recognition during LC and the potential contribution of the cross-AI system in preventing BDI through a clinical feasibility study (J-SUMMIT-C-02). METHODS: A prototype was designed to display landmarks during the preparation phase and Calot's triangle dissection. A prospective clinical feasibility study using the cross-AI system was performed in 20 LC cases. The primary endpoint of this study was the appropriateness of the detection timing of landmarks, which was assessed by an external evaluation committee (EEC). The secondary endpoint was the correctness of landmark detection and the contribution of cross-AI in preventing BDI, which were assessed based on the annotation and 4-point rubric questionnaire. RESULTS: Cross-AI-detected landmarks in 92% of the phases where the EEC considered landmarks necessary. In the questionnaire, each landmark detected by AI had high accuracy, especially the landmarks of the common bile duct and cystic duct, which were assessed at 3.78 and 3.67, respectively. In addition, the contribution to preventing BDI was relatively high at 3.65. CONCLUSIONS: The cross-AI system provided landmark detection at appropriate situations. The surgeons who previewed the model suggested that the landmark information provided by the cross-AI system may be effective in preventing BDI. Therefore, it is suggested that our system could help prevent BDI in practice. Trial registration University Hospital Medical Information Network Research Center Clinical Trial Registration System (UMIN000045731).

Enhanced phosphorylation of c-Jun by cisplatin treatment as a potential predictive biomarker for cisplatin response in combination with patient-derived tumor organoids.

Despite recent advances in sequencing technology and large-scale drug screenings employing hundreds of cell lines, the predictive accuracy of mutation-based biomarkers is still insufficient as a guide for cancer therapy. Therefore, novel types of diagnostic methods using alternative biomarkers would be highly desirable. We have hypothesized that sensitivity-specific changes in the phosphorylation of signaling molecules could be useful in this respect. Here, with the aim of developing a method for predicting the response of cancers to cisplatin using a combination of specific biomarker(s) and patient-derived tumor organoids (PDOs), we found that cisplatin-sensitive cell lines or PDOs showed enhanced phosphorylation of c-Jun (p-c-Jun) within 24 h after cisplatin treatment. We also compared the responses of 6 PDOs to cisplatin with the therapeutic effect of neoadjuvant chemotherapy (docetaxel/cisplatin/5-fluorouracil) in 6 matched patients. Mechanistically, the c-Jun induction was partly related to TNF signaling induced by cisplatin. Our data suggest that enhanced phosphorylation of c-Jun in response to cisplatin treatment could be a predictive biomarker for the efficacy of cisplatin in selected cancer patients.

Issues of cancer care in people with mental disorders as perceived by cancer care providers: A quantitative questionnaire survey.

OBJECTIVES: To reduce cancer care disparities, this study aimed to clarify the difficulties in cancer care for people with mental disorders as perceived by cancer care providers. METHODS: Cancer care providers at 17 designated cancer hospitals in Japan were surveyed using mail questionnaires. Respondents were asked to rate 29 items related to difficulties or insufficiencies in cancer care for patients with mental disorders on a five-point Likert scale. We analyzed the proportion of respondents who answered "difficult/insufficient" in each item. We also calculated the proportions of responders stratified according to the presence of psychiatric support systems within their hospitals. RESULTS: A total of 388 (58.4%) cancer care providers responded. Among the issues related to "difficulties in diagnosing and treating cancer," support for decision-making, assessment of treatment adherence, and assessment of physical symptoms were perceived as most difficult (73.5%-81.5% of respondents). Among the issues related to 'difficulties or insufficiencies in collaboration among multidisciplinary health care providers,' the issue of advance consultation and sharing information with the patient's primary psychiatric care provider was perceived as most difficult (52.2%). Among the issues related to "insufficiencies of in-hospital and community medical systems," education to provide reasonable accommodation was perceived as most insufficient (47.4%). The perceived difficulties of over half of the issues varied significantly between hospitals depending on the level of psychiatric support systems. CONCLUSIONS: This study clarified the difficulties of cancer care in patients with mental disorders as perceived by cancer care providers. Some issues may be resolved by psychiatric liaison teams.

Success rate of acquiring informed consent and barriers to participation in a randomized controlled trial of laparoscopic versus open surgery for non-curative stage IV colon cancer in Japan (JCOG1107).

BACKGROUND: Successful achievement of randomized controlled trials (RCTs) is dependent on the acquisition of informed consent (IC) from patients. The aim of this study was to prospectively calculate the proportion of participation in a surgical RCT and to identify the reasons for failed acquisition of IC. METHODS: A 50-insitution RCT was conducted to evaluate oncological outcomes of open and laparoscopic surgery for stage IV colon cancer (JCOG1107: UMIN-CTR 000000105). The success rate of obtaining IC was evaluated in eight periods between January 2013 and January 2021. In addition, reasons for failed acquisition of IC were identified from questionnaires. RESULTS: In total, 391 patients were informed of their eligibility for the trial, and 168 (42%) were randomly assigned to either the laparoscopic surgery group (n = 84) or open surgery group (n = 84). The success rate of IC acquisition ranged from 33 to 58% in three periods. The most common reasons for failed IC acquisition were the patients' preference for one approach of surgery based on recommendations from referring doctors and family members, and anxiety/unhappiness about randomization. CONCLUSIONS: The success rate of acquiring IC from patients for an RCT of laparoscopic versus open surgery for stage IV colon cancer was lower than the expected rate planned in the protocol. To obtain the planned rate, investigators should make efforts to inform patients and their families about the medical contributions a surgical RCT can make and recognize that the period in equipoise may be limited.

Artificial intelligence software available for medical devices: surgical phase recognition in laparoscopic cholecystectomy.

BACKGROUND: Surgical process modeling automatically identifies surgical phases, and further improvement in recognition accuracy is expected with deep learning. Surgical tool or time series information has been used to improve the recognition accuracy of a model. However, it is difficult to collect this information continuously intraoperatively. The present study aimed to develop a deep convolution neural network (CNN) model that correctly identifies the surgical phase during laparoscopic cholecystectomy (LC). METHODS: We divided LC into six surgical phases (P1-P6) and one redundant phase (P0). We prepared 115 LC videos and converted them to image frames at 3 fps. Three experienced doctors labeled the surgical phases in all image frames. Our deep CNN model was trained with 106 of the 115 annotation datasets and was evaluated with the remaining datasets. By depending on both the prediction probability and frequency for a certain period, we aimed for highly accurate surgical phase recognition in the operation room. RESULTS: Nine full LC videos were converted into image frames and were fed to our deep CNN model. The average accuracy, precision, and recall were 0.970, 0.855, and 0.863, respectively. CONCLUSION: The deep learning CNN model in this study successfully identified both the six surgical phases and the redundant phase, P0, which may increase the versatility of the surgical process recognition model for clinical use. We believe that this model can be used in artificial intelligence for medical devices. The degree of recognition accuracy is expected to improve with developments in advanced deep learning algorithms.

Technical and oncological safety of laparoscopic gastrectomy for gastric cancer in elderly patients ≥ 80 years old.

BACKGROUND: As the incidence of gastric cancer increases in elderly patients worldwide, laparoscopic gastrectomy (LG) for elderly patients with gastric cancer is also increasing. However, whether LG is an optimal surgical modality for elderly patients with gastric cancer remains unclear. This study aimed to evaluate the technical and oncological safety of LG for elderly patients ≥ 80 years old with gastric cancer. METHODS: Patients who received curative gastrectomy for gastric cancer from 2003 to 2015 were enrolled in the study. They were divided into the LG in elderly patients aged over 80 years (LG-E) group, open gastrectomy (OG) in elderly patients (OG-E) group, and LG in non-elderly patients < 80 years (LG-NE) group. Patients' demographics and short- and long-term outcomes, such as postoperative complications and 5-year survival rate, were compared between the three groups, retrospectively. RESULTS: The LG-E, OG-E, and LG-NE groups comprised 45, 43, and 329 patients, respectively. In the comparison between the LG-E and OG-E groups, the incidence of distal gastrectomy (DG) and the proportions of patients with pathological tumor stage T1, pathological N0, and final stage I were significantly higher in the LG-E versus OG-E group (89 vs. 56%, 76% vs. 16%, 82% vs. 37%, and 84% vs. 35%, p < 0.01, respectively). Blood loss and the incidence of overall postoperative complications in the LG-E group were significantly lower than those in the OG-E group (40 vs. 240 g, p < 0.01, and 29% vs. 53%, p < 0.05, respectively). Although the 5-year overall survival (OS) rate was not significantly different between the two groups, the 5-year disease-specific survival (DSS) rate was significantly higher in the LG-E group versus OG-E group (93% vs. 78%, p < 0.05). Overall comorbidities were significantly higher in the LG-E group versus LG-NE group, but there were no significant differences in short-term outcomes between the two groups. Further, although the 5-year OS rate was significantly lower in the LG-E group versus LG-NE group (67% vs. 87%, p < 0.01), there was no significant difference between the two groups in 5-year DSS rate. CONCLUSION: LG is technically and oncologically safe for the treatment of gastric cancer in both elderly patients aged ≥ 80 years and the non-elderly and can be an optimal surgical modality for elderly patients with gastric cancer.

Impact of COVID-19 on gastric cancer treatment in Japanese high-volume centers: a JCOG stomach cancer study group survey.

PURPOSES: The spread of coronavirus disease 2019 (COVID-19) has affected socioeconomic and healthcare systems in many countries. Accordingly, many individuals may have canceled their annual health-check programs, including esophagogastroduodenoscopy, which would have resulted in lower numbers of newly diagnosed patients with gastric cancer in comparison to other times. METHODS: Questionnaires were distributed to 62 hospitals every week from May 2020 to August 2020 (total 744) through mailing lists of the Stomach Cancer Study Group of the Japan Clinical Oncology Group. The number of patients with gastric cancer and hospital systems during the COVID-19 pandemic were surveyed. RESULTS: In total, 74% (551 out of 744) of the questionnaires were answered and analyzed. In early May, approximately 50% of hospitals had to restrict surgical slots due to the COVID-19 pandemic. However, they gradually loosened the restrictions thereafter. The number of gastrectomies was < 80% that of the same period in the previous year, and hospitals in Tokyo were seriously affected by a 50% decrease in the number of gastrectomies. CONCLUSIONS: The number of gastrectomies was lower than that in the previous year. Further multi-center follow-up studies are required to evaluate the long-term effects of COVID-19 on the clinical outcomes of patients with gastric cancer.

Early response in phosphorylation of ribosomal protein S6 is associated with sensitivity to trametinib in colorectal cancer cells.

Mutations in RAS or BRAF are associated with poor prognosis and resistance to epidermal growth factor receptor (EGFR)-targeted therapy in colorectal cancer (CRC). Despite their common ability to activate downstream genes such as MEK and ERK, the therapeutic benefit of MEK inhibitors for patients with RAS/BRAF mutant CRC is limited, highlighting the need for biomarkers to predict the efficacy of MEK inhibition. Previously, we reported that a change in phosphorylation of ribosomal protein S6 (pS6) after MEK inhibition was significantly associated with sensitivity to MEK inhibition in gastric cancer cells. Here, we investigated the value of the response in pS6 for predicting the efficacy of trametinib, a MEK inhibitor, in patients with RAS/BRAF mutant CRC using patient-derived CRC organoids. We found that a subset of CRC cell lines and organoids were sensitive to trametinib. The change in phosphorylated ERK, a downstream molecule of the RAS/RAF/MEK pathway, was not significantly associated with trametinib sensitivity. On the other hand, only those with sensitivity showed a reduction of pS6 levels in response to trametinib. The change in pS6 after trametinib treatment was detectable by Western blotting, immunohistochemistry or immunocytochemistry. We also demonstrated an impact of MEK inhibition on pS6 in vivo using a xenograft model. Our data suggest that, in combination with patient-derived organoids, immunostaining-based detection of pS6 could be useful for prediction of trametinib sensitivity.

Cancer care for people with mental disorders: A qualitative survey among cancer care and psychiatric care professionals in Japan.

OBJECTIVE: It is widely assumed that there are multiple levels (from individual to policy level) of problems involving disparities in cancer care for people with mental disorders. However, few studies have comprehensively investigated issues as perceived by medical professionals. The purpose of the present study was to identify a wide range of issues in cancer care for people with mental disorders and offer corresponding solutions for both cancer care professionals and psychiatric care professionals. METHODS: We distributed open-ended questionnaires to 754 healthcare professionals in various medical facilities, including designated cancer hospitals, psychiatric hospitals, and other local healthcare/welfare facilities. Participants were asked to describe issues in cancer care for people with mental disorders. RESULTS: Of the 754 recruited professionals, 439 (58.2%) responded to the questionnaire. Sixty-one issues were extracted and categorized into 10 categories: patient factors; isolation and lack of support; obstacles to transport; socioeconomic factors; attitudes of psychiatric professionals; medical system of psychiatric hospitals; attitudes of cancer care professionals; medical system of designated cancer hospitals; regional cancer medical systems; and lack of coordination among multidisciplinary healthcare professionals. Forty-eight specific solutions were summarized into 12 goals. CONCLUSIONS: The present study widely identified issues causing disparities in cancer care for patients with mental disorders. We found that the issues extended from the patient level to the public-policy level. Our findings suggest the need for a multidisciplinary approach that includes both cancer and psychiatric care professionals to address the gap in cancer care for people with mental disorders.

Clinical significance of sarcoid-like reaction in lymph nodes of gastric cancer patients.

BACKGROUND: Although granulomatous formation (sarcoid-like reaction [SR]) similar to sarcoidosis occasionally occurs in regional lymph nodes of malignant tumors, the pathological significance of SR is unknown. We aimed to elucidate the clinicopathological significance and prognostic relevance of SR in gastric cancer. METHODS: We evaluated 391 patients who underwent curative gastrectomy for gastric cancer between 2007 and 2016 at our hospital. The patients were divided into two groups according to presence of SR in lymph nodes, and clinicopathological factors and prognosis were compared between the two groups. RESULTS: SR was found in 67 (17.1%) of the 391 patients, and 332 (3.3%) of 10,149 lymph nodes examined. Regarding clinicopathological factors, SR-positive group showed significantly higher average age (p < 0.01) and numbers of differentiated tumors than SR-negative group (p < 0.05). Three-year overall survival rate in elderly patients aged ≥75 years was significantly more favorable in SR-positive group (n = 27, 85.2%) versus SR-negative group (n = 97, 63.4%) (p < 0.05). Immunohistochemical studies showed the predominant presence of CD68-positive macrophages for SR, with CD4/CD8-positive T cells and interleukin-10 also positive. CONCLUSION: The presence of SR in gastric cancer is frequent in elderly patients and might be a favorable indicator of prognosis. SR is suggested to reflect immune activation in the host.

Appropriate mesh size in the totally extraperitoneal repair of groin hernias based on the intraoperative measurement of the myopectineal orifice.

BACKGROUND: Insufficient coverage of the area of a possible groin hernia is an important risk factor in hernia recurrence. To prevent recurrence, it is important to use the appropriate mesh size based on the size of the myopectineal orifice (MPO), which is the weak area of the abdominal wall where inguinal hernias occur. We aimed to estimate the appropriate mesh size for groin hernias by investigating MPO size. METHODS: Four hundred and six patients underwent groin hernia repair using a totally extraperitoneal (TEP) approach at the Zeze Hospital between July 2009 and December 2017. We investigated patients' backgrounds, MPO components dimensions, and hernia recurrence, and evaluated the appropriate mesh size. RESULTS: The 359 male and 47 female patients had an average age of 63 ± 15 years. In 171, 147, and 88 cases, hernias were localized to the right, left, and bilaterally, respectively. The number of lateral, medial, femoral, and combined hernias was 317, 124, 11, and 42, respectively. The 95th percentile for the horizontal and vertical lengths in cases of hernia orifice ≥ 3 cm were 9.6 cm and 7.0 cm, respectively, while it was 9.2 cm and 6.4 cm in cases of hernia orifice < 3 cm. We added 2 cm and 3 cm to the 95th percentile for the length and width of the MPO, resulting in 13.2 × 10.4 cm and 15.6 × 13.0 cm in cases with hernia orifice < 3 cm and ≥ 3 cm, respectively. Relapse after TEP occurred in 1 patient (0.2%). CONCLUSION: The appropriate mesh size for TEP repair, derived from intraoperative MPO measurements, was estimated as 13.2 × 10.4 cm and 15.6 × 13.0 cm when the hernia orifice was < 3 cm and ≥ 3 cm, respectively. Using appropriate mesh sizes based on MPO measurement may reduce groin hernia recurrence after TEP.

Development of an artificial intelligence system using deep learning to indicate anatomical landmarks during laparoscopic cholecystectomy.

BACKGROUND: The occurrence of bile duct injury (BDI) during laparoscopic cholecystectomy (LC) is an important medical issue. Expert surgeons prevent intraoperative BDI by identifying four landmarks. The present study aimed to develop a system that outlines these landmarks on endoscopic images in real time. METHODS: An intraoperative landmark indication system was constructed using YOLOv3, which is an algorithm for object detection based on deep learning. The training datasets comprised approximately 2000 endoscopic images of the region of Calot's triangle in the gallbladder neck obtained from 76 videos of LC. The YOLOv3 learning model with the training datasets was applied to 23 videos of LC that were not used in training, to evaluate the estimation accuracy of the system to identify four landmarks: the cystic duct, common bile duct, lower edge of the left medial liver segment, and Rouviere's sulcus. Additionally, we constructed a prototype and used it in a verification experiment in an operation for a patient with cholelithiasis. RESULTS: The YOLOv3 learning model was quantitatively and subjectively evaluated in this study. The average precision values for each landmark were as follows: common bile duct: 0.320, cystic duct: 0.074, lower edge of the left medial liver segment: 0.314, and Rouviere's sulcus: 0.101. The two expert surgeons involved in the annotation confirmed consensus regarding valid indications for each landmark in 22 of the 23 LC videos. In the verification experiment, the use of the intraoperative landmark indication system made the surgical team more aware of the landmarks. CONCLUSIONS: Intraoperative landmark indication successfully identified four landmarks during LC, which may help to reduce the incidence of BDI, and thus, increase the safety of LC. The novel system proposed in the present study may prevent BDI during LC in clinical practice.

Development of Endoscopic Surgery Navigated by Artificial Intelligence.

Endoscopic surgery, which was first introduced in the late 1980s, has rapidly become widespread. However, despite its popularity, the occurrence of intraoperative organ damage has not necessarily decreased. To avoid intraoperative bile duct injury in laparoscopic cholecystectomy, which is one of the most popular procedures in endoscopic surgery, we are developing a laparoscopic surgical system that uses Artificial Intelligence (AI) to identify four anatomical landmarks (cystic duct of the gallbladder, common bile duct, lower surface of hepatic S4, and Rouviere's sulcus, related to "Calot's triangle") in real time during surgery. The development process consists of 5 steps: 1) identification of anatomical landmarks, 2) collection and creation of teaching data, 3) annotation and deep learning, 4) validation of development model, and 5) actual clinical performance evaluation. At present, anatomical landmarks can be identified with high accuracy in an actual clinical performance test in laparoscopic cholecystectomy, whereas issues for practical clinical use, such as a need to recognize the scene of surgical steps and surgical difficulties related to inflammation of the gallbladder, have also been clarified. The development of an AI-navigation system for endoscopic surgery, which could identify anatomical landmarks in real time during surgery, could be expected to support surgeons' decisions, reduce surgical complications, and contribute to improving the quality of surgical treatments.

Role of increased vascular permeability in chemotherapy-induced alopecia: In vivo imaging of the hair follicular microenvironment in mice.

Chemotherapy-induced alopecia is one of the most difficult adverse events of cancer treatment for patients. However, it is still unknown why anticancer drugs cause hair loss. We aimed to clarify the mechanism of chemotherapy-induced alopecia in mice using an in vivo imaging technique with a two-photon microscope, which enables observation of the deep reaction in the living body in real time. In this study, ICR mice were injected intraperitoneally with cyclophosphamide (120 µg/g). Changes in the hair bulb morphology, subcutaneous vessel permeability, and vessel density were evaluated by two-photon microscopy and conventional methods. In order to determine whether there is a causal relationship between vascular permeability and hair loss, we combined cyclophosphamide (50 µg/g) with subcutaneous histamine. Using two­photon microscopy and conventional examination, we confirmed that the hair bulbs became smaller, blood vessels around the hair follicle decreased, and vascular permeability increased at 24 hours after cyclophosphamide injection [corrected]. Apoptosis occurred in vascular endothelial cells around the hair follicle. Additionally, hair loss was exacerbated by temporarily enhancing vascular permeability with histamine. In conclusion, cyclophosphamide caused a decrease in vascular density and an increase in vascular permeability, therefore increased vascular permeability might be one of the causes of chemotherapy-induced alopecia.